A Deadly Spill

On April 20, 2010, an explosion on the Deepwater Horizon oil rig off the coast of Louisiana killed 11 and injured 17. The ensuing oil spill leaked 5 million barrels of oil along the Gulf Coast, making it the world's largest spill of its kind, surpassing the 1979 disaster from the Mexican oil rig, Ixtoc I, which leaked 3.3 million barrels of oil. In comparison, the 1989 Exxon Valdez disaster of more than 238,000 barrels was quite small--so small, in fact, that at the height of the Deepwater Horizon spill, its Macondo well was pumping out the equivalent of the Exxon Valdez spill total every four days.

After 86 days of gushing oil and many failed attempts to cap the leak, the flow was finally stopped on July 15 with a temporary containment cap. A "total kill" was achieved via the successful connection of one of two relief wells drilled for the purpose of delivering a permanent cement seal. The Macondo 252 well was declared dead on Sept. 19, 2010. The long-term effects on marine and coastal life are unknown, but expected to be significant.